Neverwinter Nights (NWN), produced by BioWare and published by Infogrames (now Atari), is a third-person perspective computer role-playing game that is based on third edition Dungeons & Dragons and Forgotten Realms rules. It was originally to be published by Interplay Entertainment, but the publisher`s financial difficulties forced the change. Infogrames released Neverwinter Nights for Windows on June 18, 2002. BioWare released the freely downloadable Linux Client in June 2003 (purchase of game still required). MacSoft released a Mac OS X port in August 2003. Two expansion packs were released in mid and late 2003, and a third in 2005. On October 31, 2006, the sequel Neverwinter Nights 2 was released followed by its first expansion in late 2007 and its second one at the end of 2008.

The game was based on the concept of building a internet-like model for a massively multiplayer game, allowing the end users to host the server. The belief was this model would create a potentially infinite massively multiplayer game framework. The game was named after the original Neverwinter Nights online game, the first graphical MMORPG, which ran from 1991 to 1997 on AOL.

The core release includes the game engine, a campaign that can be played as single player or multiplayer, and the Aurora toolset (for Windows only) used for creating custom content based on the same engine.

Play centers on the development of a character who becomes the ultimate hero of the story. In the original NWN scenario supplied with the game engine, the player is single-handedly responsible for defeating a powerful cult; collecting the four reagents required for stopping an insatiable plague; thwarting an attack on the city of Neverwinter, and many other side quests. The first and final chapters of the story in the official campaign deal with the city of Neverwinter itself, but the lengthy mid-story requires the player to venture into the countryside and then northward to the city of Luskan. Neverwinter is a city on the Sword Coast of Faerûn, in the Forgotten Realms campaign setting of Dungeons and Dragons.

The story begins with the player character being sent by Lady Aribeth to recover four monsters needed to make a cure for the Wailing Death, a plague that is sweeping the city of Neverwinter. With the help of Fenthick Moss, Aribeth’s love interest, and Desther, Fenthick’s friend, the player character is able to retrieve the monsters. As he is collecting these monsters, he is attacked by mysterious assassins from the cult that is behind the spreading of the plague. As the cure is being made, Castle Neverwinter is attacked by Desther’s minions. He takes the completed cure and escapes the castle, with the player character and Fenthick in pursuit. When they catch up to Desther, he surrenders after a short battle. Desther is sentenced to burn at the stake, and Fenthick, despite being unaware of Desther’s true intentions, is sentenced to hang. The player character meets up with Aribeth and they begin searching for the cult responsible for the plague and the attack on Neverwinter. With the help of Aarin Gend, Neverwinter`s spymaster, the player character retrieves diaries of dead cultists and letters from a person named Maugrim, which convince Aribeth that the cult`s headquarters are in Luskan. Aribeth goes ahead to Luskan, and the player character follows after speaking once more to Gend. After arriving in Luskan, the player character hears rumors that Aribeth is joining with the cultists. These fears are confirmed when he finds her meeting with Maugrim and Morag, Queen of the Old Ones. They seek magical relics called Words of Power. The player character retrieves all of the Words of Power except for one, held by the cult. He discovers that the words open a portal to a pocket world inside the Source Stone, where Morag and the other Old Ones are. He confronts Aribeth, and depending on how he handles the meeting, she either surrenders to the player character or he is forced to kill her. He then confronts Maugrim for the final word. He uses the words to enter the Source Stone and battle with Morag. After Morag`s death, he escapes the stone as the world inside it implodes.